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1.
《Bone and mineral》1991,12(2):123-132
The bone mineral density (BMD) of the calcaneus was measured utilizing a single energy photon absorption method in 108 women, aged 50–60 years. The women who participated in vigorous exercise two or more times a week or whose total physical activity amounted to 4 h a week had significantly higher BMD values than those who exercised less than two times a week or did less than 4 h physical activity a week. The physically active women also showed higher values for leg extension force and maximal oxygen uptake. BMD and leg extension force were positively correlated, whereas correlations between BMD and body mass, and the width of the calcaneus were negative. When other life-style variables were taken into account, such as smoking and drinking, a significant difference in BMD was found between physically active and sedentary women, but not between the smokers and non-smokers, or the drinkers and non-drinkers.  相似文献   

2.
A 32-year-old woman was referred to our hospital because of a progressive decline in her physical condition. Her medical history revealed a congenital heart defect and Down’s syndrome.  相似文献   

3.
Visual acuity was measured in 140 3–9-year-old children using Landolt’s rins with a gap in one of four orientations. The influence of surrounding additional contours on the detection of orientation of rings of a minimal visible size was studied in the same children, depending on the distance between the rings and the surrounding. The latter consisted of four bands, located symmetrically with reference to the ring. Visual acuity increased with age, reaching the adult level by approximately seven years. A deterioration of the orientation recognition was detected in all children when the surrounding was close to a ring. The distance that caused a perception deterioration decreased with age, reaching the adult level by nine years. The obtained data are discussed from the viewpoint of a possible influence of individual visual areas formed during ontogeny on task performance.  相似文献   

4.
The present study aimed to investigate the diurnal variation of postural stability, attentional capacities, and oral temperature in 5–6-year-old tennis players. A total of 24 young children were divided into two groups: Twelve tennis players with 2 years of training experience and twelve sedentary children without previous experience in any type of sport. They were asked to maintain an upright bipedal stance on a static force platform with eyes open (EO) and eyes closed (EC) at 07:00, 10:00, 14:00, and 18:00 h. Postural stability was evaluated by the center of pressure (CoP), surface area (CoPArea), CoP mean velocity (CoPVm), and Romberg’s index (RI). Oral temperature and simple reaction time (SRT) were also recorded at the beginning of each test session. Postural stability in 5–6-year-old tennis players was low at 07:00 h and improved at 10:00 h (p < 0.001); then, it worsened at 14:00 h (p < 0.001) and improved again at 18:00 h (p < 0.001) as found in sedentary children. This rhythm was also close to that of SRT in both groups. Body temperature increased significantly (p < 0.001) from the morning to the afternoon in both groups. However, the peak of postural performance, the peak of attentional capacities, and the greatest vision contribution to maintain balance observed at 18:00 h were only found in the trained group. Moreover, young tennis players were more stable (p < 0.001) and more attentive (p < 0.01) than sedentary ones at 18:00 h. The amplitude of the diurnal rhythm of CoP parameters was significantly larger (p < 0.01) in trained children compared to sedentary ones (43.1 ± 8.5 vs 31.7 ± 8.3 for the CoPArea; 27.5 ± 7.4 vs 17.7 ± 8.2 for the CoPVm). Therefore, time-of-day has a significant effect on static postural stability and attentional capacities in young tennis players with better performances in the late afternoon (habitual hour of training). Thus, we recommend planning some training sessions at 07:00 and/or 14:00 h to optimize postural stability at the time of its batyphase and to reduce the incidence of fall-related injury risks during this critical age in athletic environments.  相似文献   

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6.
This study covers a fifty-year period between 1953 and 2005 and looks at secular trends in stature, weight and sitting height sizes among French boys and girls between the ages of 3 and 11. A special modelling in function to the age and variable for each child was established so that a comparison could be made in the kinetic growth patterns over these same two periods. Statistical analysis shows a significant increase in growth, of 0.8cm per decade in stature, characterised by a certain increase in the lower limbs and the weight (0.8kg per decade) together with a proportional increase on the body mass index. Positive secular trends of this anthropometric nature are generally thanks to improved eating and sanitary habits and this study enables us to build and elaborate new standards in growth patterns essential for monitoring auxological development in 3 to 11-year-old children in the years 2000 and onwards.  相似文献   

7.
Summary Nine half-sib families of maritime pine (Pinus pinaster Aït.), of known vigor and growth pattern (monocyclic vs polycyclic), were grown under continuous light in two temperature regimes. Results of germination and development to the beginning of the second flush are reported here. Families significantly differed for mean date of germination and date of first budset. After 18 weeks of continuous light most of the seedlings had set a bud. High temperature (25° C vs 25° C/20°C) hastened first budset by approximately 5 days. However, 3 families had not reached 75% budset at the end of the experiment. Variation in date of first budset was almost exclusively explained by variation in the period between initiation of primary needles and budset. Further, 2 developmental stages could be distinguished within this period, the boundary between them being the emergence of the first secondary needles. Variation in height at first budset was mostly due to variation in growth rate, not in duration. Possible causes of early budset and implication for selection are discussed.  相似文献   

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9.
Matsushima  Miwa  Choi  Woo-Jung  Chang  Scott X. 《Plant and Soil》2012,359(1-2):375-385
Background and Aims

Phosphorus (P) mineralisation from crop residues is usually predicted from total P or carbon: phosphorus (C: P) ratios. However, these measures have limited accuracy as they do not take into account the presence of different P species that may be mineralised at different rates. In this study P speciation was determined using solution 31P nuclear magnetic resonance (NMR) spectroscopy to understand the potential fate of residue P in soils.

Methods

Mature above-ground biomass of eight different crops sampled from the field was portioned into stem, chaff and seed.

Results

The main forms of P detected in stem and chaff were orthophosphate (25–75 %), phospholipids (10–40 %) and RNA (5–30 %). Phytate was the dominant P species in seeds, and constituted up to 45 % of total P in chaff but was only detected in minor amounts (<1 %) in stem residue. The majority (65–95 %) of P in stems was water-extractable, and most of this was detected as orthophosphate. However, this includes organic P that may have been hydrolysed during the water extraction.

Conclusions

This study indicates that the majority of residue P in aboveground plant residues has the potential to be delivered to soil in a form readily available to plants and soil microorganisms.

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We present an 8-year-old girl with cleidocranial dysplasia, psychomotor developmental delay, poor wound healing and a 6p21.2–p12.3 deletion detected by aCGH. The patient was previously found to have a normal karyotype on conventional cytogenetic analysis and no RUNX2 mutation on sequence analysis. We discuss the genotype–phenotype correlation and the consequence of haploinsufficiency of CUL7, VEGFA, NFKBIE and RUNX2 in this case.  相似文献   

12.
Microcystins (MCN), β-N-methylamino-L-alanine (BMAA) and anatoxin-a were investigated in Antarctic cyanobacterial mats collected from Ross Island and the McMurdo Ice Shelf, East Antarctica during Captain Scott’s ‘Discovery’ National Antarctic Expedition (1901–1904). Ultra-performance liquid chromatography-photodiode array detection (UPLC-PDA) and tandem mass spectrometry (MS/MS) analysis were used to quantify the cyanotoxins in seven cyanobacterial mat samples. MCNs were identified in six of the mat samples at concentrations from 0.5 to 16.1 µg?g–1 dry weight. BMAA was found in one sample (528 ng?g–1 dry weight, total BMAA), as well as two BMAA isomers, 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl) glycine (AEG) in six samples up to 6.56 and 6.79 μg?g–1 dry weight, respectively. No anatoxin-a was detected. The findings confirm that MCNs, BMAA and BMAA isomers are preserved under dry herbarium conditions. The ‘Discovery’ cyanobacterial mat samples represent the oldest polar cyanobacterial samples found to contain cyanotoxins to date and provide new baseline data for cyanotoxins in Antarctic freshwater cyanobacterial mats from prior to human activity in Antarctica, the development of the ozone hole and current levels of climatic change.  相似文献   

13.
The stable carbon (C) composition of tree rings expressed as δ13C, is a measure of intrinsic water-use efficiency and can indicate the occurrence of past water shortages for tree growth. We examined δ13C in 3- to 5-year-old rings of Douglas-fir (Pseudotsuga menziesii (Mirb) Franco) trees to elucidate if decreased water supply or uptake was a critical factor in the observed growth reduction of trees competing with understory herb and shrub vegetation compared to those growing without competition. We hypothesized that there would be no differences in δ13C of earlywood in trees growing in plots with competing vegetation and those in plots receiving complete vegetation control during 5 years because earlywood formed early in the growing season when soil water was ample. We also hypothesized that δ13C in latewood which was formed during the later half of the growing season when precipitation was low, would be greater (less negative) in trees in plots without vegetation control. We then separated early and latewood from rings for three consecutive years and analyzed their δ13C composition. No significant differences in earlywood δ13C in years 3–5 were observed for trees in the two vegetation control treatments. δ13C of untreated latewood separated from wood cores was greater in 4- and 5-year-old rings of trees growing with competing vegetation compared to trees growing without vegetation competition (i.e., −25.5 vs. −26.3‰ for year 4, and −26.1 vs. −26.8‰ for year 5). Results suggest that water shortages occurred in Douglas-fir trees on this coastal Washington site in the latewood-forming portion of the growing season of years 4 and 5 in the no-vegetation control treatment. We also compared δ13C from untreated wood, crude cellulose extracted with the Diglyme–HCl method, and holocellulose extracted with toluene–ethanol to see if the extraction method would increase the sensitivity of the analysis. δ13C values from the two extraction methods were highly correlated with those from untreated samples (r 2 = 0.97, 0.98, respectively). Therefore, using untreated wood would be as effective as using crude cellulose or holocellulose to investigate δ13C patterns in young Douglas-fir.  相似文献   

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16.
A 14-year-old girl with suicidal ideation was presented to the paediatric hospital about 2 h after ingestion of 21 long-acting methylphenidate (MPH) 54-mg tablets (1,134 mg Concerta(?)). At admission signs of sympathomimetic syndrome were observed like agitation, visual hallucinations, slight hypertension, and sinus tachycardia. Treatment included prevention of absorption (30 g activated charcoal orally) and careful observation related to the overstimulation of the sympathic system. Despite the intake of charcoal, the serum concentrations of MPH were 107 and 93 ng/ml 2.5 and 22 h after ingestion of MPH tablets. No support of vital functions was necessary. The girl made a full recovery and was discharged after 3 days of care at the paediatric clinic and referred to the child and adolescent psychiatric department. Exposure to a huge overdose of long-acting MPH exhibited acute sympathomimetic toxicity but no life-threatening symptoms in this patient. Thus this case report suggests that patients intoxicated with high dose long-acting MPH formulations can recover without sequelae when managed properly.  相似文献   

17.
In 1859, the level of Lake Höytiäinen was lowered accidentally by 9.5 m and 157 km2 new land was formed. The event is marked by a 2–3 cm inwash horizon of clay and fine silt in deep-water sediments. In the sediment profile, the dry weights of 2 cm thick subsamples increase from 51 mg g–1 in the clay horizon and decrease back to 117–127 mg g–1 below the clay horizon. Below the pale clay horizon the sediment is muddy and rich in organic substances.Loss on ignition, amount of Tot.P, Tot.N and BOD7 are the highest below the clay horizon. The clay horizon has prevented mixing of the old sediment as well as aerobic decomposition of organic compounds. The high loss on ignition and the large proportion of biologically degradable organic substances in the old sediment resembles the new upper sediment of a typical central Finnish lake.The finding of a 133 year old well preserved top sediment sows that before the impact of waste waters and fertilizers, the upper sediment of the lake was rich in organic substances and nutrients. In spite of cultivation of new land later on, the new top sediment above the clay horizon is not as rich in organic substances and nutrients as the old one below it. This suggests that part of the organic substances may be mobile within the sediment and move to the uppermost sediment layer in the course of time in undisturbed lake sediments.  相似文献   

18.
HYPOTHESES: A cross-sectional study on urinary excretion of 6-sulfatoxymelatonin (aMT.6S) in young adults suggests a relation between melatonin production and body size at birth. As individual melatonin production remains stable during childhood and adolescence, this melatonin-birth size relation should also exist in children. METHODS: Daily urinary output of aMT.6S of 147 healthy white children (78 boys, 69 girls), 8 or 9 years of age, was quantified by ELISA and related to birth variable data. RESULTS: Contrary to expectation, aMT.6S output was not related to the ponderal index at birth but a moderate positive association with body mass index at the age of 8-9 years was seen. CONCLUSION: This study in children contradicts previous findings in adults. As no obvious reason can be identified for this discrepancy, further research (particularly a longitudinal study) is recommended to clarify whether birth variable data may predict melatonin production in certain circumstances during or after puberty.  相似文献   

19.
Taxonomic uncertainties of rare species often hinder effective prioritization for conservation.One such taxonomic uncertainty is the 90-year-old enigma of Fagus chienii. F. chienii was previously only known from the type specimens collected in 1935 in Pingwu County of Sichuan Province,China,and has long been thought to be on the verge of extinction.However,morphological similarities to closely related Fagus species have led many to question the taxonomic status of F. chienii.To clarify this taxo...  相似文献   

20.
In patients with osteosarcoma several causative factors are implicated in the occurrence of osteoporosis, such as no weight-bearing, pre- and post-surgical immobilization, and neoadjuvant and adjuvant chemotherapy. Nevertheless, osteoporotic fractures are a rare complication in young patients. We report the case of a spontaneous greenstick fracture of the distal tibia occurring during adjuvant chemotherapy in a 12-year-old Caucasian girl. Among the various drugs, the main role of methotrexate was investigated. A review of the literature is also presented along with a discussion about the role of preventive agents able to reduce the occurrence of osteopenia and/or osteoporosis following cancer treatment.  相似文献   

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